Spray nozzles



United States Patent Arthur Kennedy Dorman;

Frederick Albert Bartlett, Ely, England 775,766

Nov. 14, 1968 Dec. 29, 1970 The Dorman Sprayer Company Limited Ely,England a British Company Nov. 14, 1967 Great Britain Inventors Appl.No. Filed Patented Assignee Priority SPRAY NOZZLES 14 Claims, 4 DrawingFigs.

US. Cl 239/491, 239/490 Int. Cl B05b 1/34 Field of Search 239/490,

[56] References Cited UNITED STATES PATENTS l,033,603 7/1912 Manly239/490 2,668,084 2/1954 Saxton 239/491 Primary Examiner-Lloyd L. KingAssistant Examiner-Thomas C. Culp, Jr. Attorney-Holcombe, Wetherill &Brisebois ABSTRACT: This invention discloses spray nozzles for sprayingliquids, particularly those intended for agricultural and horticulturaluse in the spraying of crops and the like. The spray nozzle disclosedhas a conical chamber provided with an outlet orifice at its narrow end,at least one primary feed passage tangential to the conical wall of thechamber and at least one secondary feed passage nontangential,preferably radial, to said conical wall.

SPRAY NOZZLES The present invention relates to nozzles for sprayingliquids and more particularly to spray nozzles intended for agriculturalor horticultural use in the spraying of crops and the like.

In the field of agricultural and horticultural spraying, nozzles of thetype described in our Pat. No. 862,819 have been found to be successfulin reducing the fonnation of small spray droplets of 'under 150 microns,which are those generally sub ject to wind drift. However, it has'beenfound'that, as with other hollow cone nozzles the spray patternwill'tend to take the form of a plateau witha dip directly in line withthe noule. This makes it difficult toobtain uniform coverage over thewidth of a spray boom. Where multiple nozzles are used the obtaining ofsubstantially uniform coverage is becoming increasingly important withthe introduction of chemicals to which crops have averyylimitedresistance and'wheretherefore a more precise application of the. sprayis required.

It is therefore an object of the present inventiontoprovide a ry andsecondary feed passages to the'chamber, the arrange ment being such thatthe stream of liquid from the at least one secondary feed passageimpinges on the stream of liquid from the at least one primary feedpassage before the latter stream meets the conical wall of the chamberthechamber.

Advantageously, a separate secondary feed passage is associated witheach primary feed passage. The oreach secondary feed passage may bearranged generally radially of the conical wall of the chamber.

The liquid is preferably fed to the primary and secondary feed passagesthrough a common channel or duct.

From another aspect the invention provides a nozzle body having aconical chamber providedwith an outlet orifice at its narrow end andhaving at least one primary feed passage tangential to the conical wallof the chamber and at least one secondary feed passage generally radialto the conical wall of the chamber and a channel or duct for feedingliquid to be stituted by grooves or channels arranged substantiallytangential. to the conical walll of the/chamber 2. These passages 4communicate-with an annular feed duct or channelSthrough which theliquid to be sprayed isfed. The same surface is also provided with twosecondary feed passages 6 constituted by grooves or channels which arenarrower than those defining the primary. passages. The feed passages 6arearranged so as toextend in'a radial direction with respect to theconical chamber 2 and also communicate with the annular feed duct orchannel 5.

The nozzle structure is completed by. a back member in the form of aflat plate 7, seen in FIG. 3, which extends across the sprayed to saidat least primary and secondary feed passages.

The feed passages and the channel or duct may advantageously be formedin that surface of the nozzle body opposite the surface containing theoutlet orifice and the channel or duct may be of annular form concentricwith the conical chamber.

In one preferred form of the invention the nozzle body of generally fiatcylindrical or disclike form is provided with two tangential primaryfeed passages and two' generally radial secondary feed passagesextending betweenan annular channel or duct and the conical chamber.

The invention will now be further described, by way of ex ample, withreference to the accompanying drawings in which:

-FIG. I is a plan view of the nozzlebody of one embodiment of spraynozzle according to the invention,

FIG. 2 is a sectional view taken along .the lines 11-" of FIG. 1

FIG. 3 is a diametric section through one 'form of-spray nozzle showingthe nozzle in position in the holder, and

FIG. 4 is a section through a modified spray nozzle according to theinventor showing the nozzle in position in the holder.

Referring to FIGS. 1 and 2, the spray nozzle comprises a disc I providedwith a swirl chamber 2 of frustoconical form extending therethrough, thenarrow end of thechamber defining the outlet orifice 3.

The surface of the disc I opposite to that containing the outletorifice3 is provided with two primary feed passages 4, consurface of thedisc l opposite to-that containingthe orifice 3 and is .provided withholes 8 to permit entry. of the spray liquid to the annular ductorchannel 5.

The capacity of the nozzle is controlled by the size of the feedpassages 4 and 6.

The nozzle assembly is mounted in a holder consistingof a L body portion9 andja. retaining ring or nut l0..B ody portion 9 has acavity 1'1formed=with a seating l2,'with which the plate 7 is incontact. Thecavity communicates both with the feed channels 8 in the plate 7 andwith an inlet passage or tube 13 extending from the rear end of the bodyand isadapted to be connected to a pipe or reservoir feeding thespraying liquid to the nozzle. The retaining ring or nut 10 screws ontoan external thread 14 on the body portion and is provided with a flange15 which engages with the recessed edge 1a of the disc 1, therebyholding the disc 1 and plate 7 clamped between the flange 15 and theseating 12. The disc 1 and plate 7 are both preferably made of brass.

In operation the stream of liquid from the secondary feed passages 6,impinges upon the liquid flowing in from the primar-y feed passages 4,before the latter reach the surface of the swirl chamber 2, and therebydeflects a portion on the, spray liquid inwardly, so thatthe eventualcone of spray produced reached its target in a wider ring-of spray thanis obtained with only tangential feed passages thereby limiting the dipin the plateau spray pattern produced by the nozzle.

In the modification shown in FIG. 4 the back member is in two parts16,17. The part 16 has a platelike portion 18 which seats on lugs 19 ona shoulder 20 forming one end of the cylindri'cal portion 21 of the part17, and defines with the wall 22 of the portion 21 an annular duct orchannel 23 concentric with, and in communication with, the duct orchannel 5 in the disc I. The part 16 is also provided with a cylindricalspigot portion 24 which extends into a square-sectioned passage 25in thepart 17 leading into the interior of the cylindrical portion 21. Theliquid to be sprayed is fed to the duct or channel 23 through the spacesbetween the walls of the passage 25 and the spigot 24. In thisembodiment, the conical chamber 2 has a cylindrical portion 26 to give amoreobtuse angle to the conicalportion. In the illustrated nozzle, theangle is By modifying the proportions of the feed passages it ispossible to produce a nozzle giving a slight peak in the center of theswath.

The part 17 carries a wire gauze filter 27 to prevent sediment and thelike being fed to the orifice 2 and clogging the latter.

Advantageously the-secondary feed passages 6 are-arranged at rightangles to the diameter connecting the centers of the two tangentialprimary feed passages 4. By altering the angle of the secondary feedpassages relative to this diameter,,.the shape of the spray pattern maybevaried.

It will be appreciated that various modifications may be made withoutdeparting from the scope of the invention. For example, the'feedpassages 4 and 6 and the duct or channel 8 may be formed in the backplate.

It has been found that the droplet size can be varied greatly withvariation of pressure. When operated at a lowpressure, there arepractically no droplets of microns, but at pressures of around 50pounds, atomisation is almost complete and the average droplet size isaround 150 microns. Thisprovides two operating pressures one to givealarge droplet for spraying materials when it is important they shouldnot drift, and the second, a higher pressure to give very fine dropletswhere complete cover is required.

We claim:

1. A spray nozzle having a conical chamber provided with an outletorifice at its narrow end, and at least one primary feed passagetangential to the conical wall of the chamber, at least one secondaryfeed passage nontangential to the conical wall of the chamber, and meansfor feeding a liquid to be sprayed through said at least one primary andsecondary feed passages to the chamber, the arrangement being such thatthe stream of liquid from the at least one secondary feed passageimpinges on the stream of liquid from the at least one primary feedpassage before the latter stream meets the conical wall of the chamber.

2. A spray nozzle as defined in claim 1, wherein said at least onesecondary feed passage is generally radial to the conical wall of thechamber.

3. A spray nozzle as defined in claim 1, wherein a channel is providedfor feeding liquid to be sprayed to said at least one primary andsecondary feed passages.

4. A spray nozzle as defined in claim 3, wherein said conical chamber isformed in a nozzle body and the feed passages and the channel are formedin that surface of the nozzle body opposite the surface containing theoutlet orifice.

5. A spray nozzle as defined in claim 4, wherein said channel is ofannular form concentric with the conical chamber.

6. A spray nozzle as defined in claim 4, wherein the nozzle body is ofgenerally flat cylindrical form and is provided with two tangential feedpassages and two generally radial secondary feed passages extendingbetween the annular feed channel and the conical chamber.

7. A spray nozzle as defined in claim 6, wherein the secondary feedpassages are arranged at right angles to the diameter connecting thecenters of the two tangential primary feed passages.

8. A spray nozzle as defined in claim 1, wherein a separate secondaryfeed passage is associated with each primary feed passage. g

9. A spray nozzle as defined in claim 4, wherein the end of the conicalchamber opposite to the outlet orifice is closed by a separate backmember.

10. A spray nozzle as defined in claim 9, wherein said back member is aflat plate, extending across that surface of the nozzle body opposite tothe surface containing the outlet orifice and provided with holes topermit entry of the spray liquid to the annular channel.

11. A spray nozzle as defined in claim 9, wherein said back member is intwo parts, one part being in the form of a plate extending across theend of the conical chamber opposite to the outlet orifice and at leastthe end portions of the primary and secondary feed passages adjacent theconical chamber. and which is seated in a hollow cylindrical portion ofthe other part and defines therewith an annular channel concentric with,and in communication with, said annular channel in the nozzle body, saidother part having a passage for feeding liquid to be sprayed to theannular channel in said back member.

12. A spray nozzle as defined in claim 3, wherein said conical chamberis formed in a nozzle body and the end of the chamber opposite to theorifice is closed by a separate back member, the feed passages and thechannel being formed in said back member.

13. A spray nozzle as defined in claim 1, wherein said nozzle is mountedin a holder comprising a body portion having an inlet passage for theliquid to be sprayed and a retaining ring or nut which holds the nozzleagainst the end of said portion.

14. A spray nozzle as defined in claim 1, wherein the conical chamberincludes a cylindrical portion at its end opposite to the orifice.

